Claude Sonnet vs Opus
When to spend up within the Claude family.
/ quick answer
Sonnet is Anthropic's workhorse; Opus is the flagship. Cost delta is ~5x — worth it only on the hardest reasoning tasks. When to spend up within the Claude family.
| Dimension | Option A | Option B |
|---|---|---|
| Cost per Mtok | ~$3 in / $15 out (Sonnet) | ~$15 in / $75 out (Opus) |
| Speed | Fast (Sonnet) | Slower (Opus) |
| Best for | 90% of workloads (Sonnet) | Complex reasoning, agents (Opus) |
- →Chat, RAG, extraction → Sonnet
- →Multi-hop reasoning, autonomous agents → Opus
/ frequently asked
What is the difference in Claude Sonnet vs Opus?
Sonnet is Anthropic's workhorse; Opus is the flagship. Cost delta is ~5x — worth it only on the hardest reasoning tasks.
What are the main points of comparison?
Cost per Mtok: ~$3 in / $15 out (Sonnet) vs ~$15 in / $75 out (Opus) · Speed: Fast (Sonnet) vs Slower (Opus) · Best for: 90% of workloads (Sonnet) vs Complex reasoning, agents (Opus)
Which one should I choose?
Start on Sonnet. Escalate to Opus only where evals prove a lift that justifies the cost.
/ continue exploring
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The vocabulary this page depends on.
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Comparisons & alternatives
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- →ChatGPT vs Claude
Two leading conversational AI assistants compared across reasoning, writing, coding, and pricing.